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load cal says, heat loss of 64,000btu and 34,000 of heat gain. what would be the recommended sizing based on this for a split system, how many tons a/c and btus of gas heat?
in reguards to a/c tons what are the guidelines for the number of tons -vs- amount heat gain.(15,000=1ton, 20,000=2ton)?

fishin: Just curious. I appreciate your initiative in determining what size your home is calling for both in heating and in cooling. Are these the first steps in a do-it-yourself project, or are you going to have a contractor come in and provide you with a proposal?

Ideally, if your load is 34,000 btu for the cooling, you would want to come up with a 'match' between indoor and outdoor unit that gets you as close as possible to that number for the maximum efficiency. for example: you might find a "3" ton condensing unit when matched with a particular "3" ton coil, yields a cooling capacity of 33,500 btus. That would be a good match for your needs.

Also, keep in mind, that the recommendation provided you on an 80% afue furnace would not be the same as on a 90% afue furnace. That is, if your heating load was 64,000 btu, then the 80,000 is probably correct using an 80% furnace. However, to meet the same load using a 90% furnace, the btu input rating would be about 71,000, ideally.

Everyone has a purpose in life..........even if it's to be a bad example.

this is new construction, with a 90% VS furnace. contractor feels a/c should be sized up to 3.5 ton and 100,000 btus would be needed to push that much a/c.(i don't know any thing about that). my thinking based on the load cal. is 3.0 ton and 75,000 btus. can't an oversized furnace short cycle like an oversized a/c? as for the coils the one being used can be used with a 2 ton to a 3.5 ton compressor by changing the pin settings.

Load & EQ Selection

Originally posted by fishin this is new construction, with a 90% VS furnace. contractor feels a/c should be sized up to 3.5 ton and 100,000 btus would be needed to push that much a/c.(i don't know any thing about that). my thinking based on the load cal. is 3.0 ton and 75,000 btus. can't an oversized furnace short cycle like an oversized a/c? as for the coils the one being used can be used with a 2 ton to a 3.5 ton compressor by changing the pin settings.